Chrysler 1998 Viper RT/10 Owner's Manual page 736

14 - 22 FUEL SYSTEM
S R
D E S C R I P T I O N A N D OPERATION ( C o n t i n u e d )
CAMSHAFT POSITION SENSOR—8.0L V-10
ENGINE
The camshaft position sensor is located on the t i m -
i n g chain case/cover on the left-front side of the
engine (Fig. 2).
11ISIO S T E P
Fig. 2 Camshaft Position Sensor Location
The camshaft position sensor is used i n conjunction
w i t h the crankshaft position sensor to differentiate
between fuel injection and spark events. I t is also
used to synchronize the fuel injectors w i t h t h e i r
respective cylinders. The sensor generates electrical
pulses. These pulses (signals) are sent to the Power-
t r a i n Control Module (PCM). The P C M w i l l t h e n
determine crankshaft position from both the cam-
shaft position sensor and crankshaft position sensor.
A low and h i g h area are machined into the cam-
shaft drive gear (Fig. 3). The sensor is positioned i n
the t i m i n g gear cover so t h a t a small air gap (Fig. 3)
exists between the face of sensor and the h i g h
machined area of cam gear.
When the cam gear is rotating, the sensor w i l l
detect the machined low area. I n p u t voltage from the
sensor to the P C M w i l l then switch from a low
(approximately 0.3 volts) to a high (approximately 5
volts). When the sensor detects the h i g h machined
area, the i n p u t voltage switches back low to approx-
imately 0.3 volts.
CRANKSHAFT POSITION SENSOR—PGM INPUT
The crankshaft position sensor detects slots cut
into a disk i n the middle of the crankshaft (Fig. 4).
There are 5 sets of slots. Each set contains 2 slots,
for a total of 10 slots. Basic t i m i n g is determined by
C A M S H A F T
S P R O C K E T
Fig. 3 Camshaft Sprocket
the position of the last slot i n each group. Once the
P C M senses the last slot, i t determines crankshaft
position (next piston at TDC) from the camshaft posi-
t i o n sensor i n p u t . D u r i n g cranking, i t may take the
P C M up to one engine revolution to determine crank-
shaft position.
CRANKSHAFT
CRANKSHAFT
POSITION
SENSOR <°
\928D-25
Fig. 4 Timing Slots on Crankshaft
The P C M uses the camshaft reference sensor to
determine injector sequence. Once crankshaft posi-
t i o n has been determined, the P C M begins energizing
the injectors i n sequence. The P C M determines igni-
t i o n t i m i n g from the crankshaft t i m i n g sensor.
The crankshaft position sensor is located i n the
passengers side of the engine block, below the
exhaust manifold (Fig. 5).